Car (Motorcycle) insurance refuses to be fully comprehensive

Hello together, I like to read the forum with you, but this time I have a question myself and therefore registered myself. I describe the best way forward: On 23.3. I searched online at Check 24 and found an insurance for my new motorcycle (liability, TK and VK 1000 SB). I also got an eVB immediately by e-mail incl. the repetition that I have liability, TK and VK, the required price and where it should be debited. On 26.3. I have with the eVB the new driving And on 27.3. I get a letter from the letter box, that insurers UK etc. refuses and only assumes liability with minimum coverage. Doof! What now? I know that I am still registered in the Schufa, because a few years ago my life is a bit confused, the circumstances do nothing to the matter here. Two insurance companies had rejected me online (because Schufa vmtl.) but this company did not and got the eVB. In addition, I have to say that I also have to e years before VK was insured, in November the “old” moped was sold and now was looking for new insurers. And since the chosen company is a lot cheaper than my previous one I decided to do so. But for me it is absolutely necessary to have VK/TK, that motorcycle I bought brand new from the dealer and paid cash for 18000 euros and I did not borrow, steal or anything else…but saved in 2 years. chufa are obstructive, that I know…the time and I work hard to make it all right. What do you think I should do now because of the insurance? Do I have a special notice right, or do I have to (since I had already registered a vehicle with the conditions) insure to fulfill the contract as booked at Check24? Before I do now what I would like to ask you for advice. Thank you very much.